SARS-CoV-2 is a novel virus, and this fact accounts for the difference we see in severity along the age gradient. When we are very young, almost every virus is novel to our immune system, so we have a very robust, generic immune response. As we age, that type of response wanes, and we rely more and more on our immune system to recognize the virus. This is fine for common colds and flus because we generally see them in childhood. But for a novel virus, we rely on that generic response, which is why kids are less impacted than older folks.
Generic colds and flus evolve all the time. As adults, we still get sick from them, but those illnesses are usually not particularly severe because our immune systems have seen similar enough viruses that they can clear the evolved virus before they cause severe illness.
We should not worry too much about the variants. When we are vaccinated, the coronavirus is no longer novel to us, and the variants are more like evolved cold/flu viruses: similar to something our immune systems have seen, and hence clearable without severe illness.
Putting all the previous points together: if we are unable to completely eradicate SARS-CoV-2 (likely), it will eventually because another cold-like virus, circulating around indefinitely. This is not because it will evolve into something less virulent, but because it will no longer be novel to most humans.
This all seems plausible enough to me, but I don’t really know anything about the site (The Insight) nor the author (Dylan H. Morris), nor can I particularly evaluate the claims.
If it helps clarify some basic concepts in immunity to infection that’s fine, but the pompous hype is silly. Take the first couple of paragraphs:
SARS-CoV-2 is new to our immune systems. That makes it very dangerous. Viruses that are new to us spread faster and are more lethal than old familiar ones.
Some scientists are tempted to chalk this up to evolution. The argument is that a virus that leaves its host alive will outcompete one that kills its host. Viruses do sometimes become less deadly as they adapt to a new host species (like us), but they also sometimes become more deadly. But whether wrong or right for a given virus, this tempting just-so story can be a distraction.
Novelty is bad regardless of virus evolution.
When a virus is new, nobody possesses acquired immune protection against it.
He makes the ridiculous implication that most scientists have not heard of adaptive immunity, and he is now revealing this great truth to the world. It would have been more appropriate to frame this as an exposition of some basic scientific concepts to the layman (which is all it is), not to over-egg it as some radical new paradigm.
And it’s not a novel idea that variants are unlikely to evade vaccines completely, a quantitative reduction in efficacy is the normal expectation (as I’ve noted numerous times on here).
My read was that some scientists were focused on the evolutionary track for viruses leading to them becoming less virulent. That something that I, a nonexpert, have repeatedly read, so his point - that it’s less than and more us developing responses to the virus - is, if true, a very interesting corrective. I didn’t read it as him really saying that this idea is a ‘radical new paradigm’, but what I’m really more interested in is just… is it actually true?
No scientist is advocating waiting around for the virus to evolve. All scientific efforts are focused on “us developing responses” - i.e. vaccination.
There are important things to understand about evolution toward lower virulence, which he didn’t get into in the artilce. Any evolution toward lower virulence is a longer term phenomenon. Like all evolution, it occurs through differential survival - the more virulent form of virus has fewer “descendants” than a less virulent mutant. But the reason a more virulent form of virus will have fewer descendants is that it severely disables or kills the host so quickly that the host is not walking around intereracting with other people and infecting them. So the evolutionary path that might ultimately lead to lower virulence is not so great for the host: the end of the more virulent viral lineage takes place in dead hosts.
Of course not. I don’t think the author - or I - even said anything about anyone advocating waiting around for the virus to evolve. Not exactly sure where that came from, but suffice it to say, I’m pretty sure we’re all in agreement there.
I understand all this. Are you basically saying that you agree, and that the primary reason that viruses appear to become less virulent/deadly over time is due to change in human immune systems vs. evolutionary changes in the virus itself? If so, great!